Research And Design Of Trajectory Planning And Control System For Serial Robot

Robot has been widely used in all kinds of fields with the breakthrough of research for key technology of sensors, biomedicine, bionics, mechanism, etc. Robots would present different forms to adapt to the working environment, like micro robot used for medical examination, humanoid robot used for medical experiments, underground robot and underwater robot for special conditions, parallel robot used for fast and stable grasping, aerial robot used for aerospace, etc. Industrial serial robots are most widely applied at present, and domestic demand for industrial robots accounted for the largest proportion of total international demand, thus independent research and development of related key technology about industrial robot is of great importance. The main research content of the article is as follows:(1) The research overview about the methods and achievements on robot trajectory planning made by domestic and foreign experts was finished. The forward and inverse kinematics equations were deduced on the basis of using improved D-H coordinates system to establishthe link coordinate system model by taking the6DOF industrial robot as the research objectin. And Guangzhou CNC RB808was taken as the instance for the kinematics algorithm.(2) The algorithms of space straight line, arc, cubic spline trajectory planning in task space and interpolation of B spline in joint space were deduced.The quintic B-spline whose position, velocity, acceleration and jerk curve are all smooth was chosen as the B spline interpolation in the joint space for the control system by comparing the simulated results of cubic B-spline with the one of quintic B-spline.(3) Functional requirements for the control system were designed and the time series analysis for PLC was analyzed. The software of robot control system which is mainly composed of human-interface, soft teach box, trajectory planning, MDI motion control, soft PLC module, etc. was developed by using Microsoft Visual Studio2010on the platform of Windows with the basis of the algorithms of kinenamics and trajectory planning deduced above.(4) The system’s PID parameters were adjusted by using the UMAC controller’s own debugging software and better PID parameters which responsed well to step input were acquired. Then the velocity feedforward and the acceleration feedforward were added, and sine function input was carried out to get better velocity and acceleration feedforward factors. Experiment for cubic spline trajectory planning on robot’s end actuator verified the feasibility of system software.The function software of robot control system which was researched and developed in this article could meet the demand for the point-to-point and contouring motion and it would lay a strong foundation for the research of accuracy control of the robot system.